Organ Systems Notes
- Nervous System
- Made up of two main systems:
1. _central ___ - brain and spinal cord
2. _peripheral______- nerves extending from the spinal cord to the rest of the best
- Nerve cells are called _neurons______.
Draw a picture of a nerve cell and label A) Dendrite, B) Cell Body, and C) Axon:
- Explain the process by which a nerve signal travels from one neuron to the next:
Nerve signals have both an electrical and chemical component. Nerve signals are sent through the following procedure:
1) An electrical impulse called an__Action Potential______travels down the axon.
2) The Action Potential cannot cross the __Synapse (gap)______between the 2 neurons; therefore, vesicles containing a ___chemical messenger called a neurotransmitter___ fuse with the axon membrane.
3) These vesicles containing the neurotransmitter are released into the _synapse____ in order transmit the information from one neuron to the next.
4) __Dendrites______receive these neurotransmitters and each dendrite relays this information to the _Cell Body______.
5) The cell body translates this chemical information into an electrical __Action Potential______which is sent down the axon.
6) This process repeats itself as a nerve signal is sent to and from the brain and various locations in the body.
Draw two nerve cells here and diagram the relaying of a signal between the two by a) labeling the direction of an action potential and where it flows, b) the synapse, c) where neurotransmitters would be
Lobes of the brain:
- There are _4____ lobes in the brain.
Below you will identify each lobe and tell the function / location of each:
1)_Frontal______-
Location – Forehead
Function – The “human part of the brain”; Responsible for higher order thinking, creativity, personality, etc.
2)__Parietal______-
Location – Back, top of the head
Function –deciphering information from the senses
3)_Temporal ______-
Location – Side of head (temple)
Function - Hearing
4)_Occipital______-
Location – Back, bottom of the head
Function – Sight
- Immune
Function – Fight off infection
Major organs –White blood cells, lymphatic system
- Reproductive
Function – Create offspring
Major Organs–Testicles, Ovaries, etc.
_Gametes______- Sex cells that are __haploid______(meaning they have only 1 set of chromosomes)
__Somatic______- Body cells that are _diploid______( meaning that they have 2 sets of each chromosome / homologous chromosomes)
- Circulatory
Functions – distribute nutrients / oxygen throughout the body
2 types of circulation –
1)__pulmonary______- Blood flowing between the heart and lungs
2)___systemic______- blood flowing between the heart and the rest of the body
3 types of blood vessels:
1)__artery______- carry blow AWAY from the heart
2)___vein______- carry blood TOWARD the heart
3)___capillary______- in between arteries and veins; very thin so oxygen and nutrients can cross the vessel walls to be dropped off throughout the body
Chambers of the Heart:
__atria______- receive blood
__ventricles______- pump blood
The __left______side has blood that contains oxygen
The _____right______side has blood that has NO oxygen
Path of blood through the body:
1)Blood that is used throughout the body comes back to the __right atria______through the _superior vena cavae______and _inferior vena cavae______.
2)Blood then goes to the __right ventricle______where it is pumped through the __pulmonary artery______to the _lungs______to pick up oxygen.
3)The blood then comes___back__to the ___left atria______through the ____pulmonary vein______.
4)Blood then comes to the __left ventricle______where it is pumped to the rest of the body through the ____aorta______.
- Respiratory
Functions – supply the body with Oxygen and release carbon dioxide
Major Organs – Lungs, Bronchial tubes, alveoli
- Endocrine
Functions – Produce hormones (that direct the other systems)
Major Organs –hypothalamus, thyroid, pancreas (creates insulin and glucagon), and any “gland” word
- Digestive
Functions – supply body with fuel to create ATP
Flow of food through digestive system:
- Food is chewed in the _mouth___ where it is both ____chemically______and __mechanically______digested.
- It then travels through the __esophagus______to the _stomach______where it is __broken down______.
- _Bile______made by the ___liver______is added to the food to help break down ___fats______.
- The __gall bladder______stores excess bile made by the liver.
- The food leaves the stomach and travels through the __small intestine_____ where ___nutrients are reabsorbed into the bloodstream______.
- The food then passes through the _large intestine______where ____water is reabsorbed into the bloodstream______.
- The food then exits the body through the _____rectum______.
- Urinary
Functions – maintain fluid balance, pH, and to remove waste
Major organs –kidneys, ureter, urethra, urinary bladder
- Skeletal
Functions – provide stability for body, posture, and protect inner organs
Bones are held to other bones by ___ligaments______.
- Muscle
Functions – allow for movement
Muscles are held to bones by ___tendons______.
The three types of muscle tissues are:
- ___smooth______
- ___skeletal______
- ___cardiac______
Types of tissues
- Epithelial – Covers body surfaces (your skin and the skin of your organs)
- Connective tissue
a) Loose Connective – Holds together tissues and organs
b)Fibrous Connective – Tendons (holds bone to muscle) and Ligaments (Bone to Bone)
c)Adipose – Fats cells
d)Cartilage – In between bones to cushion them and keep them from rubbing against each other
e)Bone –
f)Blood – Connects whole body by transporting nutrients and oxygen throughout
- Muscle
- Skeletal muscle – striped muscle that is connected to bone (by tendons); responsible for VOLUNTARY movement
- Cardiac muscle – striped like skeletal but it is also branched; muscle in your heart
- Smooth muscle – it IS NOT striped (it looks smooth); located in your organs; responsible for INVOLUNTARY movement
- Nervous tissue – Brain and nerve tissue; responsible for regulating everything else in the body
3 main parts of a neuron:
- Dendrites – At the start of the cell; receive information (neurotransmitters) from previous neuron
- Cell body – contains the nucleus; adds together all the information gathered by the dendrites and sends a signal down the neuron
- Axon – section of the neuron where the Action potential (nerve signal) travels down to send the signal to the next neuron